Automatic heat-alarm.



-J G. SGHLGHTNER. AUTOMATIG HEAT ALARM.

APPLICATION FILED APR. 25, 19121' l1,076,157." 'flatented 0@t.21,1913

f) er 'Amm/ver unirti) srATEs .PATENT orinci.

r9-Sere e SCHLCHTNER. 0i @savana rosa t auroivia'rie rinitis-ALARM.

To all whom, t may conce/m NER, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Automatic Heat-Alarms, of which thefellowing is a specification.

rlhis invention has for its object to provide a thermometric indicator or alarm 'device which may be utilized to give warning of excessive heat in-varous adaptations, as in buildings, in case of fire, in powder maga Zinesv and the like, in ease ofspontaneous combustion, or in the'bearings of machines, diie to friction, and which in .any of the adaptations -to which it may thus be put willl be eiiieient, reliabl'e (to such a degree that it will not prematurely operate, as when moved or shaken as an incident to its use, and yet will assuredly operate when a predetermined temperature is reached), simple bling of its parts.

in construction and capable of ready assem- Ainong-the salient features of my invention are the peculiar form of its receptacle for a thermo-expansible electro-conductive iiuid,'sueli as mercury, whereby a very ap preciable exposure of surface of such fluid to the heat of the atmosphere, 'transmitted through the wall of such receptacle, is aceoinplished, and at the same time the said 4fluid is maintained more or less quiescent,

notwithstanding the device may be shaken or otherwise moved suiiiciently so that otherwise the fluid would be Caused to close the electric circuit in which the device is instituted; the peculiar form and arrangement of the terminals of the velectric circuitwith relation to said receptacle and the circuit closing fiuid; and the manner in which the various parts of the device are assembled.

l have fully illustrated the invention in the annexed drawing, wherein,

Figure l is a sectional view thereof with the electric circuit and alarm with which it is associated shown diagrammatically; Fig. 2

is a plan view of the device with the mount-Q ing a. removed and the circuit omitted; and.

Fig. 3 isl a sectional view on line aime of Fig. 1.

a; may be any suitable mounting. It is herein shown a'shaving a stein o for attaching it to some support, as Z), and is preferably formed of porcelain er the like,

Specification of' Lettersvlatent.

tially coincident with though these details are wholly immaterial. Its body part c is annular, and preferably has an internal screw-thread CZ, thus forming a socket.

c is a receptacle for the mercury f-or other thermo-expansible electro-conduetive liquid'. It isl preferably made' of glass,

ythough this not essential; glass is preferred because it is transparent, permitting' visual inspection of the interior of theA receptacle, especially in assembling the parts and adjusting the apparatus te the conditions under which it is to operate. The receptacle e is made up of a plurality of hollow disks g, arranged one above the other, and tubular necks h, preferably vertically alined wit each other and alternating and formed integral with the disks. The upperinost chamber g and the uppermost neck 'h have eachy greater vertical dimension'than time other disks and necks, respectively, as shown. The uppermost chamber has a throat or mouth 21 axially alined with the necks 7L, and- O somewhat larger diameter.

A metallic piece y', including agscrewthreaded outer bushing 71: and a depending interior part Z, is screwed into the socket c. Into the annular space existing between bushing 7c and the depending part Z is fitted the mouth 71 of receptacle-e, such mouth being embedded ina llinc' of cement m which, upon setting, becomes locked iiiplace by virtue of the screw-threading of. bushing 'fv.' the exterior-ly threaded piece forms a part of a plug projecting from the receptacle member which is screwed into the socketmember, as shown in the drawings;

The part Z has its portion n., which dcpends well below the bottom of socket c, tapering and formed with an open end whosel 'edge is toothed or serrated, as indicated by `0. In the assembled relation of the parts, the points of the teeth or serrations o lie in a horizontal plane substanthat where the upper neck 7L merges into the upper 'chamber g, the diameter'of the lower extremity of portion fn, being about equal lto the. internal diameter of said neck. Thusabefore the mercury can enter the uppermost chamber it must. contact with the lower serrated end of portion nf Axially coincident with the bushing and within the' same is a metal cylindrical socket p having a downwardly depending wire orv l rat-cated oet. 21, 1913. Application filed April 2,5a 1912- -elal No. 693,151.

other form of metallic extension .f/ which` protrudcs 'from the lower end of the part Z ot' said bushing into'the uppermost neck ZL. A filling of no11-electro-conductive cement or the like 1^ occupies the space ol part Z and holds the socket in place. To support the cement#l upon its introduction and while setting a fiber or other non-conducting disk a may be'jammed into' the lower end of part being penetrated by the extcnsionq.

'15 designates an electric circuit in which' is a bell or similar device u, one end of the wire included in said Icircuit being attached toi'a bindingfpost /v on the piece j and thc other lo a binding-post il: carried by a split plug ai which may be removably fitted into the socket p,

The mercuryis introduced into Athe receptacle e at a temperature which corresponds to that at which the apparatusis to operate; at such temperature, the mercury should' have contact with both the serrated lower end of the part Z of the bushing and the extension q of the socket p, so sufiicient mercury is introduced to bring its top surface underthe temperature-condition designated in the same horizontal plane as the tips of the serrations of part Z. The Abushing, the socket and thelling g` of cement having been preferably first assembled, the mouth ofthe receptacle is embedded in the filling ot cement m, having first, however',l charged thespace of' the receptacle above the mercury with compressed air.

In use, should the temperature of the place or part which is to be protected exceed that predetermined the mercury will rise until, the lower end of extension g being submerged, it contacts with the serrated lower end of the part Z, thus closing the cire cuit and sounding the alarm. The peculiar form of the receptacle plays an important part in stabilizing the mercury, since only a limitedpart of the mercury, z'. e., that directly occupying the vertical passage inI the receptacle which is constituted by the series of necks h, is :tree to rise, the rest being confined by lateral recesses extending from said passage'theyoutlying interiors of the chambers g. Since the lower end of the terminal formed by part Z extends downwardly at least as far as the plane'of the upper end ofneck h, the normally exposed surface-area of the mercury up to the moment of the closing of the circuitin the proper or contemplated performance of the device is limited, enhancing 'theedect of preventing such motion of the mercury, due to jarring or shocks or shaking the device. as would cause it to-touch the terminal Z and close the circuit prematurely, such as might occur, for instance, ifthe mercury were allowed to enter the uppermostchamber Z1, before' assuming the intended Contact with thek terminal Z and there expose ay con novara? the device' is further insured thus: lt' the mere touching of the mercury with the extreme .points of the serrated ylower end 'of part Z should not be Vsuflicient (the end of extension Q being already submerged in the mercury)l effectively to close the circuit the mercury will work its way through the openings between the serrations until a good contact is' produced. On the other hand, the lower end of part Z being well spaced from the terminal g any possible adhesion of globules or particles of mercury insuti-v cient quantity to close the circuitis prevented. To insure the efficiency of the de vice, metals for the terminals g and o are employed with which y. mercury will not amalgamate.

Having thus fully described my invention," what I claim as new and desire to secure by Letters Patent is l l. ln combination, a suitable receptacle, a thermo-oxpansible electro-conductive fluid arranged in said receptacle, an alarm, an electric circuit including the alarm and having a break therein and terminals at said break both depending into said receptacle to different depths, one surrounding the other and having downwardly extending teeth or serrations, substantially as described.

2. In combination', a suitable receptacle having an upwardly extending neck, a thermo-expansible electro-conductive fluid arranged in said receptacle, an alarm, an y electric circuit including the alarm and havving a break therein and terminals at said break both depending into said receptacle to different depths, one surrounding the other and having downward projections eX- tending at least as far as the horizontal `plane of the upper extremity of said neck,

substantially as described.

3. In combination, a mounting, an annularmetallic member forming a terminal and having an exterior hollow portion secured in the mounting and an interior/J depending hollow portion spaced from said exterior portion, a bodyof insulating/material occupying the space of said interior portion, a body of cement occupying/'the space between said exterior andinterior portions, another metallic member embeddedin the body of insulating material, an alarm, an electric-circuit including the' alarm and having a break therein and also having its ends at said break attached to said members,

and a. receptacle having a mouth embedded in saidA cement body, substantially as described.

4. In an apparatus of the class described,

.a thermo-expansble electro-conductive fluid and a, hollow receptacle Containing said fluid, said receptacle comprising a plurality of superposed hollow disks and relativelv limited tubular necks connecting said disks,

substantially as described.l 10

In testimony whereof I al'lx my signature in presence of two Witnesses.

JOSEPH G. SGHLGHTNER.

Witnesses't JOHN MURPHY, JAMES F. OHARA. 

